Western Digital's Caviar Black hard drive

While Seagate grabs headlines as the market share leader in the hard drive world, lately we've been more impressed with Western Digital's portfolio. The company's Black and Blue Scorpios fared very well in our latest mobile storage round-up, outpacing rival Momentus drives from Seagate. Then there's the radically redesigned VelociRaptor, which recently raised the bar for Serial ATA hard drive performance while riding a bold new form factor. For enthusiasts, the Caviar SE16 640GB offers the best blend of performance, capacity, noise levels, and overall value of any 7,200-RPM desktop drive. And let's not forget the power-efficient and nearly silent "GreenPower" Caviar GP drives with terabyte capacities.

The GreenPower line's prodigiously low power consumption is achieved by dialing back spindle speeds, but that sacrifices performance, and it ultimately cost WD the title of fastest terabyte on the block. Somewhat surprisingly, Western Digital was apparently in no hurry spinning a terabyte up to full speed. Indeed, the new Caviar Black 1TB is the last 7,200-RPM drive to reach the terabyte mark, arriving a year after Hitachi broke the seal and well behind entries from Seagate and even Samsung.

So was the Caviar Black 1TB worth the wait? Can WD extend its hot streak and add the terabyte performance crown to its already impressive palmarès? Read on to find out.

Back in Black
Western Digital recently juggled its hard drive naming scheme in an attempt to simplify things for consumers. On the desktop, GreenPower Caviar GP drives have become the Caviar Green Line. Caviar Blue drives fill out the middle of the range as mainstream products, while Caviar Black variants take over the high end. The Caviar Black, then, is Western Digital's flagship desktop offering at 7,200RPMthe best of the breed, or so one would hope.

Of course, WD's recent string of successes leaves plenty of room for optimism. After all, the Caviar Black is based on the same platter technology as the seriously quick Caviar SE16 640GB. That drive squeezes 320GB onto each of its two platters, but the Black does a little better, boosting platter capacity to 334GB. Increasing the Black's areal density allows the drive to reach the terabyte mark with only three platters, which reduces the load on the drive motor and can lead to quieter operation and better reliability. Higher areal densities can also improve performance by allowing the drive head to access more data over shorter physical distances.

Maximum external
transfer rate

300MB/s

Sustained data rate

145MB/s

Average read seek
time

4.2ms

Spindle speed

7,200 RPM

Available
capacities

750GB, 1TB

Cache size

32MB

Platter size

334GB

Idle power consumption

7.8W

Read/write power
consumption

8.4W

Idle acoustics

24 dBA

Seek acoustics

29-33 dBA

Warranty length

Five years

According to Western Digital, the Black's platters are simply an evolved version of what's available in the 640GB Caviar SE16. Upgrades have been applied elsewhere on the drive, too, including a bump in onboard cache to 32MB. Western Digital has long maintained that its performance profiling shows little benefit to jumping from 16 to 32MB of cachea belief so strong that even the new VelociRaptor has a 16MB cache. However, with terabyte drives from Hitachi, Samsung, and Seagate all featuring 32MB caches, I suspect the Caviar Black's cache size was increased just to keep up with the Joneses. At the very least, workloads that would easily saturate a 16MB cache won't be a problem for the Black, however rare and unusual those workloads might be.

Speaking of the VelociRaptor, the Caviar Black inherits one new trick from Western Digital's 10K-RPM mini-monster. The Black features not one, but two processors, effectively doubling the horsepower it has available to calculate how to move, collect, and cache data on the drive.

As usual, WD has fiddled with the firmware for this latest Caviar. Most drive manufacturers seem to optimize drives for higher sustained throughput, but Western Digital points out that going too far can compromise performance with more random workloads. Rather than being tuned for a one-way drag race, the Black's firmware has been groomed to handle a mix of read and write requests that should better represent real-world workloads.

Another new feature of the Caviar Black is NoTouch drive head technology. NoTouch encompasses the IntelliSeek just-in-time head delivery scheme WD has been using for a while now. It also denotes the fact that the drive head moves completely off the disk at idle, never resting on it. Keeping the drive head away from the platters lowers the chance of a catastrophic head crash, and according to Western Digital, it also improves the drive's overall longevity.

As a member of the executive Black club, the latest terabyte Caviar inherits WD's swanky StableTrac motor tech. StableTrac secures the drive shaft at both ends of the disk, reducing vibrations and any noise they might have generated.

Western Digital has kicked up the warranty coverage for its Black line, too. The drives are covered by a five-year pact that equals the coverage the company offers with its enterprise-class products (and the five-year warranty available with all of Seagate's desktop drives).